1. Field of the Present Disclosure
The invention relates generally to insulated textile-like materials and more particularly to aerogel based textile like materials having excellent insulating properties as well as high flexibility.
2. Description of Related Art Including Information Disclosed Under 37 CFR 1.97 and 1.98
The important insulating properties of aerogel materials are well known. The use of composite structures, that is, multi-layered bonded assemblies are known for the advantages they provide using the benefits of several layers. Such materials have been, and continue to be, applied in the clothing and packaging industries. They provide light weight, effective thermal insulating properties, ease of manufacture and adaptability to a wide range of applications.
The terms “aerogel,” “aerogels,” “aerogel materials” as used herein, refer to gels containing air as a dispersion medium in a broad sense, and include aerogels, xerogels and cryogels in a more narrow sense. Furthermore, the chemical composition of aerogels, in the meaning of this disclosure can be inorganic, organic, and combinations of inorganic and organic structures. Further, such aerogels can be opacified with compounds such as, but not limited to: B4C, Diatomite, Manganese ferrite, MnO, NiO, SnO, Ag2O, Bi2O3, TiC, WC, carbon black, titanium oxide, iron titanium oxide, zirconium silicate, zirconium oxide, iron oxide, manganese dioxide, iron titanium oxide, chromium oxide, silicon carbide or mixtures thereof. The aforementioned fiber-reinforced aerogels can be reinforced with polymer-based fibers such as fibers of polyester and/or inorganic fibers such as carbon, quartz, and similar materials where such fibers are in forms such as: batting, mat, felt, microfiber, chopped fiber and any other form, and combinations of these forms.
Examples of inorganic aerogels include, silica, titania, zirconia, alumina, hafnia, yttria and ceria. Organic aerogels can be based on, compounds such as, urethanes, resorcinol formaldehydes, polyimide, polyacrylates, chitosan, polymethyl methacrylate, members of the acrylate family of oligomers, trialkoxysilylterminated polydimethylsiloxane, polyoxyalkylene, polyurethane, polybutadiane, melanime-formaldehyde, phenol-furfural, polyethers, carbons and combinations thereof. Examples of organic-inorganic hybrid aerogels are, silica-PMMA, silica-chitosan, silica-polyether and combinations thereof.
Published US patent applications 2005/0192367 and 2005/0192366 teach exclusively of such hybrid organic-inorganic materials and are hereby incorporated herein by reference in their entirety.
Insulating aerogel materials such as might be used in the present invention have a fiber-reinforced aerogel composite formed by pouring a pre-gel mixture comprising a gel precursor into a fibrous matrix, wherein the mixture then gels. Subsequently the mixture is dried to form the composite, which is typically referred to as an “aerogel blanket.” Alternatively, the composite may be prepared by adding fibers, or a fibrous matrix, to the pre-gel mixture comprising gel precursors followed by drying. Drying may be accomplished using a variety of methods known in the art. U.S. Pat. No. 6,670,402 teaches drying via rapid solvent exchange inside wet gels using supercritical CO2 by injecting supercritical, rather than liquid CO2 into an extractor that has been pre-heated and pre-pressurized to substantially supercritical conditions. U.S. Pat. No. 5,962,539 describes a process for obtaining an aerogel from a polymeric material that is in the form of a sol-gel in an organic solvent, by exchanging the organic solvent for a fluid having a critical temperature below a temperature of polymer decomposition, and supercritically drying the fluid sol-gel. U.S. Pat. No. 6,315,971 discloses a processes for producing gel compositions comprising: drying a wet gel comprising gel solids and a drying agent to remove the drying agent under drying conditions sufficient to minimize shrinkage of the gel during drying. U.S. Pat. No. 5,420,168 describes a process whereby Resorcinol/Formaldehyde aerogels can be manufactured using a simple air drying procedure. Finally, U.S. Pat. No. 5,565,142 describes drying techniques at vacuum to below super-critical pressures using surface modifying agents.